Personally I have always kept to 200 follows max per day across all accounts.

RT'ing and using hashtags relating to big time tweeters in your niche can also help well. Look into setting up RSS feeds on your Twitter account from Top Niche Leaders from their Blogs using TwitterFeed.com. In advanced settings you can include a suffix something like "via @biguserid. Works good for me. Have over 20,000 followers on my @Steve_SEO_UK account and I'm not endlessly clicking follow, follow, follow every day. Hope this helps.

Maybe you should start following fewer people when the account is recently created. And you should add some content to it on a daily basis or once every 2-3 days. Start following less than 100 people on the first day of creating your account. That way you shouldn't raise any flags from Twitter.

My understanding is 100 to be followed everyday and not more than that. I am successful in getting good number of followers and have crossed 1300 followers in about 15 days.

I think 100 is the right number to follow everyday. And just following will not keep your followers intact, but you have to post every day and use the hash tag to get your required geo location followers.

- be active and tweet at the right time
- post interesting content ( tweet something that catch your followers interest)
- tweet trending topics
- follow people with several active followers and @mention them
-use hashtags in your post to make it searchable.

You should not follow more number of followers continuously.
That will consider as a spam. So , some accounts will be suspended automatically.
Keep twitter account in your website , if you have one.
You can increase your followers by this method.
And you can advertise twitter profile url using ppc methods.
If you are following less number of people , follow only same interest people like you.

So that you can increase your followers naturally.
Post tweets regularly, for not loosing your existing followers.

There are so many ways to increase followers! I have written 60 great tips on increasing followers! Check my signature, as for mass following mmm lol I believe 200 per day follows / unfollows are safe levels for new accounts. Be careful though!! Better use some of the other methods in my guide

The best way to get QUALITY followers (ie. not bots) is to be active on Twitter. Post tweets. Retweet other posts you find interesting in your niche. Reply to people. Engage people. Contribute value to your followers.

1. Create a Flashy Profile Picture.
2. Give a meaningful and a solid Bio.
3. Have a Flashy Background which displays your message.

Once you have done these steps let's move out to the world-

1. Search for your niche in search box - like internet Marketing
Ok
2. Now find out someone from the list who has lot of followers.
3. Go yo his Twitter account.
4. Follow his followers to the tune of around 40 in the beginning and later can scale up. Do not be aggressive as that ruin your reputation as your followers must me more than your following always and have a long term prospective if you have 40 followers in a single account daily then it is like 120 targeted followers for you in single day. So be patient and follow this rule.

Ok

Post so equality tweets. You must post 2 out of 10 tweets which has a link to your squeeze page.

The Most Important Part - You should work like a solution provider. Do not run after sales initially just build relationship first and ten sales will automatically happen and money would flow automatically